Waste gas purification tower

The invention discloses a waste gas purification tower. The tower comprises a tower body, a gas inlet pipe and a blow-off pipe are arranged on the tower body, a grid, a spraying pipe, an activated carbon layer and a demister are arranged in the tower body, a liquid discharging hopper is arranged in the tower body and located below the gas inlet pipe, the liquid discharging hopper comprises a liquid discharging opening, and a transmission device is arranged below the liquid discharging hopper; and the transmission device comprises an impeller, a rotating shaft, a rotating disc, a pull rope, a fixing rod, a rotating wheel and a downward pressing block. Sewage falls down to act on the impeller to promote the impeller to rotate to generate power, the downward pressing block is driven to move up and down, dusts and particles contained in sewage at the orifice of the blow-off pipe are uniformly beaten, and when the downward pressing block moves upwards, part of the sewage can be driven to flow back within a small r